Iranians shop beneath a poster for an unlikely bestseller DVD of a speech called 'The Art of Making Love' by cleric Hossein Dehnavi, in a religious bookstore in Tehran, Iran, on June 3. The video has been a runaway hit in the Islamic Republic, where Mr. Dehnavi calls lovemaking a 'form of worship' like jihad.

“Love” may be one of the most heavily used words in Persian literature. Famous poets Rumi, Hafez, and Sa’adi obsessed about “eshq” centuries ago, though their words most often referred to divine and spiritual emotions.

Discussion of physical love was another matter. As in many cultures, it was long a taboo subject, and the advent of Iran’s 1979 Islamic revolution did little to change that. The trend for decades has, in fact, been evident in annual police crackdowns that target women showing too much hair, or boy-girl handholding in the streets.

So it might be a surprise that one of the hottest-selling DVDs in Tehran – at least at souvenir stores that cater for Shiite religious pilgrims to the Shah Abdol-Azim shrine, south of the capital – is one that seems to encourage something of a sexual revolution, Shiite-style.

Advertising posters proclaim, “The Art of Making Love,” and show cleric Hossein Dehnavi looking like any other young seminary-trained holy man in Iran, bespectacled and bearded, wearing a turban and religious robes.

Yet Mr. Dehnavi’s comparisons of lovemaking to jihad have ensured that, since its release in late May, religious bookshops here run out of their new stock of DVDs every afternoon.

The video is of a theological speech that Dehnavi gave during a seminar, to a gathering of newlyweds and others, in the shrine city of Mashhad in northeast Iran. It is called: “Improving the Skill of Making Love: The Peace and Pleasure in Matrimonial Life.”

In a nation where sexual dissatisfaction ranks as one reason for a high rate of divorce, even guidance from a cleric appears welcome to some.

“According to our religion, eshqbazi [lovemaking] is a form of worship,” says Dehnavi in the video.

“We have quotes from the 12 [Shiite] Imams saying that having sex with your wife is just like jihad, fighting for the sake of Allah,” says Dehnavi. “Unfortunately, some people believe sexual relationships are ugly. No, it is not an ugly behavior in Islam, it is a divine behavior and it is even a religious obligation to properly make love.”

During the video, the camera sometimes pans across the conservatively dressed listeners, where some lower their heads out of shyness at the subject matter. When there is a positive reaction from one member of the group to the linkage between lovemaking and religion, the cleric points him out and says he “gets the message.”

Alireza, a teenage shopkeeper in the bazaar near the shrine south of Tehran, has never seen such high demand. The $2 DVD seems out of place among his standard fare of mourning ceremonies, revolutionary videos, and religious dirges favored by Iran’s pious poor and ideologues.

These days, virtually every shop in this bazaar sells Dehnavi’s treatise on love, and hangs the eye-catching poster to bring in customers.

“This is the last piece I am selling you now,” says Alireza. “We had dozens in the morning, but all sold out. It’s rare; none of our other DVDs has been a hit like this. All other stores in this bazaar are the same. You can’t find it on the shelves in the afternoon.”

Morality police – and advanced family planning programs

The Islamic Republic has long had an intriguingly mixed influence over the sexuality of its citizens.

On the one hand, the morality police crack down on so-called “loose” women wearing “bad hijab.” But at the same time, Iran also has one of the most advanced family planning programs in the world, with subsidized birth control pills, vasectomy clinics, and condoms, and mandatory education programs for students.

Temporary marriages are common, and can be valid for days or many years; “newlyweds” are given a certificate to mark their new status. Sex-change operations, surprisingly, have also had official sanction for decades.

In the DVD, Dehnavi offers reassuring words about the religious centrality of love.

“In Islam having love, making love, of course in a family framework [marriage] is not a bad thing, it is a sacred, holy act and is advised by all religious leaders including the Prophet,” says Dehnavi. "We in Iran and Islam are shy, but the couple in love must enjoy being with each other."

Translating such guidance into matrimonial bliss would not now be easy for Babak, a 37-year-old engineer working in Tehran who separated from his wife after three years of marriage. A big problem and the root of later arguments, he said, was their sexual relationship.

Last month, the semi-official Mehr news agency referred to “recent research” indicating that 90 percent of married women in Iran were looking for a relationship beyond their marriage because of “emotional dissatisfaction.” Some 96 percent of married men were also “looking for [another] woman outside the home,” citing “sexual dissatisfaction.”

Dehnavi, who has previously presented a family TV program, said the issue of lovemaking brought up a question: “Now let’s ask why Islam emphasizes this,” he says on the DVD. “When a man and woman get together and make love, it elevates their loving emotions and is a real element of constancy and continuity of their matrimonial life …it is the sign of deep and true love.”